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Ultima MOS-5 Detector
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Figure 11: Relay Reset
•
The relays can be reset via the remote reset input terminals on TB2. Connect a
normally open switch between terminal TB2-7 and TB2-8. Closing the switch
momentarily will reset the relays. MSA explosion-proof switch, P/N 30051-1 can be
used for this purpose. See Section 9.5 for ordering instructions.
•
The relays can be reset via the Modbus Interface (Section 8.8.22).
•
The relays can be reset via the HART communication.
NOTE:
Red LEDs above and below the digital display indicate that the alarm and warn relays
are active. Latching relays can only be reset if the gas concentration has fallen below
the respective relay set point.
4.4 User Selectable Options
The Ultima MOS-5 Intelligent Sensor includes many selectable options to provide the user with
the most flexible H
2
S gas detector possible. These options include selectable sensor range,
warn and alarm relay set points and configuration, HART communications and Modbus
communications settings. These allow the unit to operate with a wide variety of PLC and DCS
systems. The following sections explain the available options and how they can be customized.
A flow diagram is included to help the user in understanding the process of reviewing and
changing the available options (Figure 12).
NOTE:
If the unit was ordered without relays, HART, or Modbus communications, changing the
relay, HART, or Modbus settings will have no effect on the operation of the unit.
Modbus
•
Dual
Redundant
Modbus
•
Single Modbus and HART
HART
•
HART is a Master to Slave -One to One communication channel.